Thanks to a new collaboration between the two, Zimbra users together with Asterisk now have voice capability from within their Zimbra-based calendars, e-mails and contacts. Zimbra users can click-to-call individual numbers, initiate conference calls by selecting groups of contacts or a meeting entry on a calendar and can also directly access voicemail.

Kevin P. Fleming senior software engineer at Digium and co-maintainer of Asterisk, said that the Zimbra integration is the first such collaboration tool to be integrated in an Asterisk-specific way. Fleming explained the integration enables users to initiate multi-party conference calls without having to go through any "machinations" to get there.

"They just sent the appropriate commands to the server and it instantiates a bunch of outbound calls, including one back to you, and dumps everyone into a conference bridge, " Fleming told internetnews.com.

Since it's a PBX and not just a simple softphone integration, users will get to take advantage of Asterisk's dialplan functionality, which can connect VoIP, landline, mobile and PBX extension users together.

"When you send the request to the Asterisk server, it makes the decision to reach the target number, whether that's an extension number that can be reached across the internal network or a cell phone number or whatever," Fleming said.

To access the Asterisk functionality, all a Zimbra user needs to do is install the new Asterisk Zimlet, and of course they'll need to have Asterisk installed. A Zimlet is essentially a Web Services mashup, which integrates Zimbra with third-party information systems and content.

At present, neither Zimbra nor Asterisk's lead sponsor Digium have any plans to directly monetize the new offering.

"This is about trying to find ways to add value to both communities and to connect the two communities," John Robb, vice president of marketing and product management at Zimbra, told internetnews.com.

Robb characterized the collaboration between Zimbra and Asterisk as being "obvious" since both are very transparent.

"The integration of e-mail, voicemail and calling are the primary drivers for value and that's what our focus has been on," Robb said. "Because both platforms are open, we can move quickly to respond."